Orion, the Hunter

This page was last amended on 3rd December, 2007

The above photograph of Orion was taken by Society Secretary Debra Huzzard on the evening of 3rd March 2007at Shrawley, Worcestershire, where our membership had assembled to see the total Lunar eclipse. It was taken with, as she puts it, her "basic digital camera".

The camera was mounted on a tripod and the image is obviously a time-exposure, evidenced by slight star trails. The photograph does, nonetheless, show a great deal of detail, including, peeping through the uppermost branches of the tree, the stars making up Orion's shield or bow. The red colour of Betelgeuse does not come out very well - possibly because of slight over-exposure - despite some digital enhancing using Adobe Photoshop.

The distinctive "V"-shaped open cluster, the Hyades, that makes up part of Taurus, is clearly visible in the top right-hand corner of the picture, and the red colour of Aldebaran (the brightest star in that region) is, like that of Betelgeuse, somewhat washed out. However, all-in-all, this does show that you don't necessarily need specialist equipment to take very acceptable astronomical photographs. Compare it with the star-chart below.

Orion is one of the most distinctive constellations, perhaps because of both its size and its brightness (it contains four of the 30 brightest stars in the entire sky), as well as the fact that it is one of the few constellations that does not require too much imagination to "see" what it represents.

The brightest part of the constellation is the central hour-glass shape, but it also contains a representation of Orion's raised right arm holding a club, and a shield, or perhaps a bow, held in Orion's left hand.

Orion's left shoulder is represented by the red supergiant Betelgeuse, (alpha Orionis), magnitude +0.45. Despite its "alpha" designation, it's not the brightest star in Orion - more of that later. It is very large, however, and if it were to be placed at the centre of our Solar System it would swallow up Mercury, Venus, the Earth and perhaps even Mars.

Moving clockwise around the constellation, Orion's head is represented by Meissa, (lambda Orionis), magnitude 3.39. It is a binary, with a 5.5 magnitude companion.

The right shoulder is represented by Bellatrix (gamma Orionis), magnitude 1.64, and Orion's left foot is the brightest star in Orion, Rigel (beta Orionis), magnitude +0.18, the seventh brightest star in the sky. It is a visual binary, but its companion is much fainter at magnitude 10.4.

The right foot is represented by Saiph (kappa Orionis) at magnitude 2.06.

Three stars representing Orion's "belt" run across the hour-glass' waist; from left to right Alnitak, (zeta Orionis), magnitude 1.74, a triple star whose primary is blue- white and whose secondary is red, Alnilam, (epsilon Orionis) magnitude 1.69, and Mintaka, (delta Orionis), magnitude 2.25.

There are three Messier objects in Orion, the best-known of which is M42, the Orion Nebula. It is a large gas/dust nebula lit by the surrounding stars, that is easily visible to the naked eye. A medium telescope will reveal the Trapezium - four stars held together by common gravity.

Another well-known nebula, the Horsehead Nebula, is visible in medium to large telescopes, but it is better treated as a photographic object.